Lowcoder 2.4.10 flaw lets attackers steal cross-tenant query data

An attacker with a standard admin or developer account on a shared Lowcoder instance can now access private data from other organizations. The flaw, tracked as CVE-2026-16753, allows users to bypass authorization boundaries within the platform’s Query Library feature. According to CERT/CC, this vulnerability exists in Lowcoder version 2.4.10 and exposes sensitive query configurations and backend data sources to unauthorized parties.

In plain English

Lowcoder is an open-source tool that lets users build web applications using a visual interface rather than writing code manually. Each project uses a centralized Query Library to store data connections and queries for reuse. The problem arises because the API service managing this library fails to verify which organization owns the requested data. It checks if the user has permission within their own group but ignores whether they belong to the group owning the target resource.

The background

The Carnegie Mellon University CERT/CC published an advisory confirming the issue in version 2.4.10. The advisory states that the LibraryQuery API lacks organization-scope checks at two specific endpoints: metadata retrieval and query execution. While the system enforces role-based access, it only validates roles against the user’s own organization. This gap allows any authenticated user with admin or dev privileges to traverse tenant boundaries and interact with other groups’ data libraries on the same instance.

What changes now

Teams using multi-tenant Lowcoder deployments face immediate risk of cross-tenant data exposure. The advisory notes that attackers can read the full Domain Specific Language of other organizations’ queries and execute them directly. This can lead to data exfiltration, modification, or destruction. Additionally, attackers might abuse paid data sources using another tenant’s financial resources. CERT/CC reports that Lowcoder could not be reached for coordination, and no official security update has been confirmed yet.

What made it possible

This incident illustrates a common failure in multi-tenant application design where access controls are applied inconsistently across service layers. Security teams usually encounter this when role validation occurs at the user level but not at the resource ownership level. The weakness serves the initial access or privilege escalation stage of an intrusion by allowing lateral movement between isolated accounts. Organizations should check whether their platforms enforce strict scope boundaries on all API endpoints, ensuring that users cannot interact with resources outside their defined tenant context regardless of their internal permissions.

What to do and how to stay safe: Lowcoder

• Restrict access to the affected Query Library API endpoints to trusted users only until an official update is released.
• Review and limit the number of accounts with admin or dev roles, especially in environments allowing self-signup.
• Consider isolating multi-tenant deployments into separate instances to prevent cross-organization data access.
• Implement custom organization-level authorization checks for metadata retrieval and query execution if source-code modification is possible.

Step-by-step guide: Automatic Updates Mistakes That Leave Systems Exposed

General security guidance from the RedTeam Monitor newsroom. It is not confirmed advice from the organisations named in this story.

Frequently asked questions

Which version of Lowcoder is affected by this vulnerability?

The vulnerability affects Lowcoder version 2.4.10, according to the CERT/CC advisory.

Is there a patch available for CVE-2026-16753?

No fix has been confirmed yet, as the vendor could not be reached for coordination.

Who reported this vulnerability to CERT/CC?

Louis Sanchez, a member of Voke Cyber, reported the vulnerability.